1. Field of the Invention
The present invention relates generally to an apparatus for vaporizing a liquid to produce a fogging effect, and more particularly, to an apparatus for vaporizing a liquid to produce a fogging effect by using ultrasonic energy produced by a piezo-electric element.
2. Description of the Related Art
FIG. 1 is a diagram of a typical fogging unit. As shown in FIG. 1, the traditional fogging unit 100 is a self-contained unit comprised of a piezo-electric element 101 for generating ultrasonic energy, and electric circuitry 102 for converting a supplied power to a level to operate the piezo-electric element. Electric circuitry 102 is typically connected to an external power source via electric cord 103 and converts line voltage into a supply voltage to operate the piezo-electric element.
FIG. 2 is a diagram of a fogging unit 200. In addition to the elements of FIG. 1, shown in FIG. 2 is a lamp module 201 attached to the typical fogging unit. The lamp module 201 receives an operating voltage from electric cord 103 through a second electric circuitry 202. The electric circuitry driving the lamp and the electric circuitry driving the piezo-electric element can be combined in the same unit. The fogging units of FIGS. 1 and 2 are available to the consumer as shown, or packaged as a consumer misting product as shown in FIG. 3.
FIG. 3 is a diagram depicting a typical consumer misting product 300 containing the fogging unit 200 unit of FIG. 2. Shown in FIG. 3 are fogging unit 200, bowl 301, water 302, splash guard 303 and splash guard frame 304. Fogging unit 200 is positioned inside of the bowl 301, with electric cord 103 extending out of the bowl 301. Splash guard 303 is positioned above piezo-electric element 101 for preventing water from splashing out of the bowl during operation. The splash guard 303 can be, for example, a rock, a ball, or a plastic sphere. Splash guard 303 is held in position by splash guard frame 304. Splash guard frame 304 is either affixed to the bowl or designed to support itself. Finally, water 302 is placed into the bowl 301 at a level above the piezo-electric element 101 but below the splash guard 303. Also shown is lamp 201 for providing atmospheric lighting to the misting product 300.
In operation, when power is supplied to fogging unit 200, the electric circuitry (not shown) converts the power to a predetermined level and, in turn, supplies the converted power to piezo-electric element 101 and lamp 201. Piezo-electric element 101 begins to vibrate and emit ultrasonic energy at levels designed to vaporize the water 302. As the water 302 is vaporized, fog is produced, which spills over the edge of the bowl 301. For proper fog spillage, the length of the open end of the bowl 301 is generally required to be greater than the height of the bowl 301. Combined with the light illuminated from lamp 201, the fog produces a soothing visual effect.
While the above-described misting produce does produce illuminated fog, there are several problems with the above-described system. First, as the fogging unit is required to be submerged in water during operation, any internal electronics must be potted and sealed. The potting refers to a process wherein electronics that are to be exposed to water are encased in a material that prevents water from contacting the electronics. This process permanently encases the electronics, prevents future repair, and adds additional costs to the overall manufacturing process. The sealing refers to enclosing the potted electronics into a case that provides a space to connect the potted electronics with external elements, namely, the piezo-electric element, lamp, and power cord. This case must also be sealed and heavy enough to allow the entire unit to remain submerged. Generally, the case is manufactured from a metal to provide the needed weight, adding additional costs to the overall unit. All of the connections must be waterproof and sealed. As the potting and sealing processes do not allow for repair of the fogging unit, replacement of the entire fogging unit is required upon any malfunction.
In addition to the above problems, several others exist. The unsightly power cord must be draped over the side of the bowl from the inside to the outside, detracting from the overall soothing visual effect. Also, with the lamp positioned below the water level, much of the light is lost to diffraction in the water. Finally, the submersion of the fogging unit can result in an electric shock hazard if the electric components of the fogging unit become exposed to the water.